12 Synthetic Filter Discs for" Wide Mouth" 87mm jar lids Used for Mushroom Cultivation: Amazon.com: Industrial & Scientific
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Amazon.com: Synthetic Filter Paper Stickers 20 mm Filter Patch Sticker 0.25 µm Filter Paper Circles for Mushroom Cultivation Wide Mouth Jar Lids (96 Pieces) : Home & Kitchen
How to make filtered lids for grain spawn jars - YouTube
DuPont Tyvek 127S Series Coveralls | Fisher Scientific